1. Field of the Invention
The present invention is directed to a grease extractor, and more particularly to a grease extractor incorporating a uniquely configured fan which causes a forced flow of grease laden air through and outwardly of the fan in order to separate grease from the grease laden air and deposit the grease on a trap member disposed downstream of the fan for effective removal of the grease from the grease laden air.
2. Description of the Prior Art
In a factory operating lathes and grinders, there has been a potential hazard of contaminating environment with grease employed in the operation of the lathes and grinder. To remove the grease from grease laden air, it has been proposed in U.S. patent application Ser. No. 687,156 filed on Apr. 18, 1991 to provide a combination of a centrifugal fan, a trap member and a membrane filter. In this prior art device, the centrifugal fan generates a force flow of the air to introduce the grease laden air inwardly and flow it radially outwardly for collision against the trap member disposed radially outwardly of the fan in order to deposit the grease for separation and recovery of the grease thereat. The forced flow of the air is reflected at the trap member and redirected through the membrane filter disposed downstream of the fan in order to trap the grease still carried on the air. However, there remains a problem in that since the centrifugal fan generates substantially only the radial outward flow from its fan surface toward the trap member, the trap member on which the grease is deposited is constantly exposed to the force air flow so that the grease once deposited on the trap member is likely to be again carried on the force air flow. Such occurrence is responsible for lowering separation efficiency and therefore necessitates the membrane filter downstream of the trap member in order to seize the grease effectively. With the addition of the membrane filter, the device suffers from a correspondingly increased flow resistance and fails to enhance a flow amount per unit time required for efficient grease separation, particularly in a large facility.